Claim: Vaccines do not contain peanut oil
Excipients for vaccines and other intramuscular injections in the past contained peanut oil, and other common foods that have become allergens for some people.
An excipient is a supposedly neutral substance that acts as a suspension for vaccines and other injections.
In the past, peanut oil and beeswax1 were used as excipients for intramuscular injections.
Could these be the cause of peanut and bee-sting allergies? I could find no studies looking at this possibility (for some reason studies on this particular subject are particularly hard to find full-text for online), however the reverse case scenario, where someone who has an existing allergy might be exposed to an excipient, has been studied.
An adjuvant is a substance added to a vaccine to increase the immune reaction to the original pathogen. I wonder why adjuvants don’t also cause an immune reaction to the excipient as well?
Lately the pharma companies seem to have been looking further afield for particularly rare adjuvants; perhaps this is to avoid immune reactions to more common substances?
In the 1994 Handbook of pharmaceutical excipients Peanut oil is listed as an excipient for pharmaceutical intramuscular injects.
A 1999 manual of excipients, Pharmaceutical excipients : characterization by IR, Raman, and NMR spectroscopy, lists peanut oil as well:
Excipients still include peanut oil for some injectable medications. It says here that they believe peanut oil is not allergenic because there are no reports of allergic reactions to peanut oil in medications:
https://www.jacionline.org/article/S0091-6749(14)00432-1/fulltext
Or perhaps people who are allergic to peanut oil are far more aware of the possible side effect of death, which makes them avoid medications that include peanut oil as an excipient?
According to the CDC Peanut oil does not seem to be included as a vaccine excipient any longer, nor is it included in the list of adjuvants.
So it is true that since the 1940s Peanut Oil has been an excipient, a supposedly inert substance used as a carrier for intramuscular injections, and this included vaccines.
Vinu’s Newsletter has looked into this as well; he includes some more references here:
CHASE HF, BHATTACHARYA BK. Prolongation of curare action with a peanut oil and beeswax vehicle. Federation Proceedings. 1948 Mar;7(1 Pt 1):211. PMID: 18857929.
Any injected protein will cause the development of an allergy (sensitization) to that protein as Charles Richet found.
Subsequent injection will cause an allergic reaction (elicitation).
https://www.nobelprize.org/prizes/medicine/1913/richet/lecture/
It takes tiny quantities of protein to cause sensitization but you need larger amounts to cause an elicitation. Purified peanut oil is still contaminated with peanut protein. It is enough to sensitize. It may not be enough to elicit a reaction.